1. Field of the Invention
The invention relates to a light emitting diode, and more particularly related to a light emitting diode package structure.
2. Description of the Related Art
Light emitting diodes (LEDs) have many advantages including high brightness, low volume, low power consumption and long life and they are used in a variety of display products. The lighting principle of LED is caused by a combination of electrons and holes in an LED when a voltage is applied to the LED. The combination releases photons from the diode.
In general, referring to FIG. 1a, the conventional light emitting diode package structure comprises a lead frame 10 and a molding plastic body 12. Next, a chip 14 is disposed on the lead frame 10, and a wire 16 is used to achieve an electrical connection. Finally, a transparent package resin 18 is filled to cover the chip 14 and the wire 16, thus the conventional light emitting diode package structure is obtained, as shown in FIG. 1b. In order to improve the adhesion ability of the plastic body 12 to the package resin 18, generally hydrophilic polymers are used for the plastic body 12. However, due to the hydrophilic property of the plastic body 12, the package resin may spill out to form overflowing residues 20 over the outer surface due to intermolecular interaction, as shown in FIG. 1c. Furthermore, since the plastic body 12 is completely constituted by hydrophilic polymer, peeling of the package resin from the plastic body 12 can be observed due to moisture absorption as exposed in the atmosphere for a relative duration of use.
Therefore, it is desirable to introduce a novel light emitting diode package structure that improves the aforementioned problems.